Mt. St. Helens erupts

MOUNT ST. HELENS, Wash. (AP) - Mount St. Helens belched a thick plume of white steam and ash today,

more than a week after a flurry of earthquakes first warned an eruption was on the way.

"This is exactly the kind of event we've been predicting," said U.S. Geological Survey scientist Cynthia Gardner.

Steam frequently rises from a lava dome in the crater of the volcano, which erupted with devastating force and killed 57 people on May 18, 1980.

But there had been no eruptions in 18 years.

A few minutes after noon, the steam cloud poured from the southern edge of a nearly 1,000-foot-tall lava dome in the volcano's crater, where a

large section of glacier had fractured and risen

since Thursday afternoon. After about 20 minutes, the mountain calmed and the plume quickly dissipated, heading south-southwest.

Small earthquakes had been occurring continuously in the crater since Sept. 23. They grew steadily stronger, finally reaching a magnitude of 3.3 Thursday and Friday,

but the earthquakes quit after the eruption, said University of Washington seismologist Tony Qamar.

"That makes us think this is the end of the eruption," Qamar said. "All this buildup was leading to that relatively small eruption."

Mike Fergus, a spokesman with the Federal Aviation Administration in Seattle, said the plume had reached 16,000 feet in altitude, but did not know whether any planes would need to be rerouted.